U.S. patent application number 11/474324 was filed with the patent office on 2006-12-28 for power output apparatus, vehicle equipped with power output apparatus, and control method of power output apparatus.
This patent application is currently assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA. Invention is credited to Zenichiro Mashiki.
Application Number | 20060289211 11/474324 |
Document ID | / |
Family ID | 36968379 |
Filed Date | 2006-12-28 |
United States Patent
Application |
20060289211 |
Kind Code |
A1 |
Mashiki; Zenichiro |
December 28, 2006 |
Power output apparatus, vehicle equipped with power output
apparatus, and control method of power output apparatus
Abstract
The drive control of the invention sets a rotation speed Ni for
in-cylinder injection according to an operation curve used in
operation of an engine with fuel injection from only in-cylinder
fuel injection valves and a rotation speed Np for port injection
according to an operation curve used in operation of the engine
with fuel injection from only port fuel injection valves (steps
S150 and S160). The drive control subsequently sets a target
rotation speed Ne* and a target torque Te* of the engine by
distributing the rotation speed Ni for in-cylinder injection and
the rotation speed Np for port injection by an allocation rate k of
in-cylinder fuel injection to port fuel injection (step S170). The
drive control then sets torque commands Tm1* and Tm2* of two motors
and controls the engine and the two motors to drive the engine at a
specific drive point defined by the target rotation speed Ne* and
the target torque Te* and to ensure output of a torque demand Tr*
to a ring gear shaft or a driveshaft (steps S180 through S220).
This arrangement attains efficient and appropriate operation of the
engine.
Inventors: |
Mashiki; Zenichiro;
(Aichi-ken, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 19928
ALEXANDRIA
VA
22320
US
|
Assignee: |
TOYOTA JIDOSHA KABUSHIKI
KAISHA
Toyota-shi
JP
|
Family ID: |
36968379 |
Appl. No.: |
11/474324 |
Filed: |
June 26, 2006 |
Current U.S.
Class: |
180/65.28 ;
123/431; 180/65.235 |
Current CPC
Class: |
B60W 10/06 20130101;
Y10T 477/20 20150115; B60W 10/08 20130101; Y02T 10/62 20130101;
B60L 2240/441 20130101; Y10T 477/26 20150115; Y02T 10/64 20130101;
Y02T 10/70 20130101; B60L 2220/42 20130101; F02D 41/3094 20130101;
Y02T 10/72 20130101; B60L 50/62 20190201; B60W 20/00 20130101; B60L
2250/26 20130101; B60W 20/10 20130101; F02D 2250/18 20130101; B60L
2240/421 20130101; B60W 2710/0616 20130101; Y10T 477/23 20150115;
B60L 2240/443 20130101; B60L 2240/423 20130101; B60K 6/445
20130101; B60L 2240/12 20130101; B60L 15/2045 20130101; Y02T
10/7072 20130101 |
Class at
Publication: |
180/065.2 ;
123/431 |
International
Class: |
B60K 6/02 20060101
B60K006/02; F02D 41/30 20060101 F02D041/30 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 27, 2005 |
JP |
2005-186678 |
Claims
1. A power output apparatus that outputs power to a driveshaft,
said power output apparatus comprising: an internal combustion
engine that outputs power and has an in-cylinder fuel injection
valve for injecting a fuel into a cylinder and a port fuel
injection valve for injecting the fuel in an intake port; a torque
conversion unit that converts the output power of the internal
combustion engine by torque conversion and transmits the converted
power to the driveshaft; a target driving force setting module that
sets a target driving force to be output to the driveshaft; a
target power setting module that sets a target power to be output
from the internal combustion engine, based on the set target
driving force; a target operating state setting module that sets a
target operating state of the internal combustion engine, based on
the set target power, a specified allocation rate of fuel injection
from the in-cylinder fuel injection valve to fuel injection from
the port fuel injection valve, a first constraint, and a second
constraint, where the first constraint is imposed on an operating
state of the internal combustion engine with shared fuel injection
from the in-cylinder fuel injection valve and from the port fuel
injection valve at a predetermined first allocation rate, and the
second constraint is imposed on the operating state of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at a
predetermined second allocation rate different from the first
allocation rate; and a control module that controls the internal
combustion engine and the torque conversion unit to drive the
internal combustion engine in the target operating state with fuel
injection at the specified allocation rate and to ensure output of
the target driving force to the driveshaft.
2. A power output apparatus in accordance with claim 1, wherein
said target operating state setting module sets the target
operating state of the internal combustion engine by distributing a
first operating state and a second operating state of the internal
combustion engine by a ratio of the specified allocation rate to
the predetermined first allocation rate and a ratio of the
specified allocation rate to the predetermined second allocation
rate, where the first operating state of the internal combustion
engine is set based on the first constraint and the target power
and the second operating state of the internal combustion engine is
set based on the second constraint and the target power.
3. A power output apparatus in accordance with claim 1, wherein
each of the first constraint and the second constraint includes
multiple restrictions with regard to multiple conditions, and said
target operating state setting module sets the target operating
state of the internal combustion engine, based on a certain
restriction included in the first constraint and a corresponding
restriction included in the second constraint with regard to a
selected condition among the multiple conditions.
4. A power output apparatus in accordance with claim 3, wherein the
multiple restrictions include at least one of an efficient
operation restriction for efficient operation of the internal
combustion engine and a high torque output restriction for output
of a high torque from the internal combustion engine.
5. A power output apparatus in accordance with claim 1, wherein the
first constraint regards operation of the internal combustion
engine with fuel injection from only the in-cylinder fuel injection
valve, and the second constraint regards operation of the internal
combustion engine with fuel injection from only the port fuel
injection valve.
6. A power output apparatus in accordance with claim 1, wherein the
torque conversion unit is a continuously variable transmission, and
said control module varies a change gear ratio of the torque
conversion unit to drive and rotate the internal combustion engine
at a rotation speed specified by the set target operating
state.
7. A power output apparatus in accordance with claim 1, wherein the
torque conversion unit comprises: an electric power-mechanical
power input output mechanism that is connected to an output shaft
of the internal combustion engine and to the driveshaft and outputs
at least part of the output power of the internal combustion engine
to the driveshaft through input and output of electric power and
mechanical power; a motor that inputs and outputs power from and to
the driveshaft; and an accumulator unit that receives and transmits
electric power from and to the electric power-mechanical power
input output mechanism and the motor, wherein said control module
controls the internal combustion engine, the electric
power-mechanical power input output mechanism, and the motor to
drive the internal combustion engine in the target operating state
and to ensure output of a driving force equivalent to the target
driving force to the driveshaft.
8. A power output apparatus in accordance with claim 7, wherein the
electric power-mechanical power input output mechanism comprises: a
three shaft-type power input output module that is linked to three
shafts, the output shaft of the internal combustion engine, the
driveshaft, and a rotating shaft, and inputs and outputs power from
and to a residual one shaft based on powers input from and output
to any two shafts among the three shafts; and a generator that
inputs and outputs power from and to the rotating shaft.
9. A vehicle, said vehicle comprising: an internal combustion
engine that outputs power and has an in-cylinder fuel injection
valve for injecting a fuel into a cylinder and a port fuel
injection valve for injecting the fuel in an intake port; a torque
conversion unit that converts the output power of the internal
combustion engine by torque conversion and transmits the converted
power to the driveshaft connected to an axle; a target driving
force setting module that sets a target driving force to be output
to the driveshaft; a target power setting module that sets a target
power to be output from the internal combustion engine, based on
the set target driving force; a target operating state setting
module that sets a target operating state of the internal
combustion engine, based on the set target power, a specified
allocation rate of fuel injection from the in-cylinder fuel
injection valve to fuel injection from the port fuel injection
valve, a first constraint, and a second constraint, where the first
constraint is imposed on an operating state of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at a
predetermined first allocation rate, and the second constraint is
imposed on the operating state of the internal combustion engine
with shared fuel injection from the in-cylinder fuel injection
valve and from the port fuel injection valve at a predetermined
second allocation rate different from the first allocation rate;
and a control module that controls the internal combustion engine
and the torque conversion unit to drive the internal combustion
engine in the target operating state with fuel injection at the
specified allocation rate and to ensure output of the target
driving force to the driveshaft.
10. A vehicle in accordance with claim 9, wherein said target
operating state setting module sets the target operating state of
the internal combustion engine by distributing a first operating
state and a second operating state of the internal combustion
engine by a ratio of the specified allocation rate to the
predetermined first allocation rate and a ratio of the specified
allocation rate to the predetermined second allocation rate, where
the first operating state of the internal combustion engine is set
based on the first constraint and the target power and the second
operating state of the internal combustion engine is set based on
the second constraint and the target power.
11. A vehicle in accordance with claim 9, wherein each of the first
constraint and the second constraint includes multiple restrictions
with regard to multiple conditions, and said target operating state
setting module sets the target operating state of the internal
combustion engine, based on a certain restriction included in the
first constraint and a corresponding restriction included in the
second constraint with regard to a selected condition among the
multiple conditions.
12. A vehicle in accordance with claim 9, wherein the first
constraint regards operation of the internal combustion engine with
fuel injection from only the in-cylinder fuel injection valve, and
the second constraint regards operation of the internal combustion
engine with fuel injection from only the port fuel injection
valve.
13. A vehicle in accordance with claim 9, wherein the torque
conversion unit is a continuously variable transmission, and said
control module varies a change gear ratio of the torque conversion
unit to drive and rotate the internal combustion engine at a
rotation speed specified by the set target operating state.
14. A vehicle in accordance with claim 9, wherein the torque
conversion unit comprises: an electric power-mechanical power input
output mechanism that is connected to an output shaft of the
internal combustion engine and to the driveshaft and outputs at
least part of the output power of the internal combustion engine to
the driveshaft through input and output of electric power and
mechanical power; a motor that inputs and outputs power from and to
the driveshaft; and an accumulator unit that receives and transmits
electric power from and to the electric power-mechanical power
input output mechanism and the motor, wherein said control module
controls the internal combustion engine, the electric
power-mechanical power input output mechanism, and the motor to
drive the internal combustion engine in the target operating state
and to ensure output of a driving force equivalent to the target
driving force to the driveshaft.
15. A vehicle in accordance with claim 14, wherein the electric
power-mechanical power input output mechanism comprises: a three
shaft-type power input output module that is linked to three
shafts, the output shaft of the internal combustion engine, the
driveshaft, and a rotating shaft, and inputs and outputs power from
and to a residual one shaft based on powers input from and output
to any two shafts among the three shafts; and a generator that
inputs and outputs power from and to the rotating shaft.
16. A control method of a power output apparatus, said power output
apparatus comprising: an internal combustion engine that outputs
power and has an in-cylinder fuel injection valve for injecting a
fuel into a cylinder and a port fuel injection valve for injecting
the fuel in an intake port; and a torque conversion unit that
converts the output power of the internal combustion engine by
torque conversion and transmits the converted power to a
driveshaft, said control method comprising the steps of: (a)
setting a target driving force to be output to the driveshaft, and
setting a target power to be output from the internal combustion
engine based on the set target driving force; (b) setting a target
operating state of the internal combustion engine, based on the set
target power, a specified allocation rate of fuel injection from
the in-cylinder fuel injection valve to fuel injection from the
port fuel injection valve, a first constraint, and a second
constraint, where the first constraint is imposed on an operating
state of the internal combustion engine with shared fuel injection
from the in-cylinder fuel injection valve and from the port fuel
injection valve at a predetermined first allocation rate, and the
second constraint is imposed on the operating state of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at a
predetermined second allocation rate different from the first
allocation rate; and (c) controlling the internal combustion engine
and the torque conversion unit to drive the internal combustion
engine in the target operating state with fuel injection at the
specified allocation rate and to ensure output of the target
driving force to the driveshaft.
17. A control method of a power output apparatus in accordance with
claim 16, wherein said step (b) sets the target operating state of
the internal combustion engine by distributing a first operating
state and a second operating state of the internal combustion
engine by a ratio of the specified allocation rate to the
predetermined first allocation rate and a ratio of the specified
allocation rate to the predetermined second allocation rate, where
the first operating state of the internal combustion engine is set
based on the first constraint and the target power and the second
operating state of the internal combustion engine is set based on
the second constraint and the target power.
18. A control method of a power output apparatus in accordance with
claim 16, wherein each of the first constraint and the second
constraint includes multiple restrictions with regard to multiple
conditions, and said step (b) sets the target operating state of
the internal combustion engine, based on a certain restriction
included in the first constraint and a corresponding restriction
included in the second constraint with regard to a selected
condition among the multiple conditions.
19. A control method of a power output apparatus in accordance with
claim 16, wherein the first constraint regards operation of the
internal combustion engine with fuel injection from only the
in-cylinder fuel injection valve, and the second constraint regards
operation of the internal combustion engine with fuel injection
from only the port fuel injection valve.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a power output apparatus, a
vehicle equipped with the power output apparatus, and a control
method of the power output apparatus.
[0003] 2. Description of the Prior Art
[0004] One proposed power output apparatus to be mounted on a
vehicle has an engine with in-cylinder fuel injection valves for
injecting the fuel into cylinders and a toroidal continuously
variable transmission (see, for example, Japanese Patent Laid-Open
Gazette No. 2000-52817). This power output apparatus sets a target
torque of the engine and a target input shaft rotation speed of the
transmission, based on the driving state of the vehicle and a
target driving force that varies with a variation in driving state.
The target torque of the engine and the target input shaft rotation
speed of the transmission vary according to the state of
combustion, which reflects a variation in air-fuel ratio of the
air-fuel mixture supplied to the engine. The engine and the
continuously variable transmission are controlled with allocation
of a driving force defined by the target torque of the engine and
the target input shaft rotation speed of the transmission. Such
control aims to drive the engine under the operating conditions of
the optimum fuel consumption.
[0005] Another proposed power output apparatus has an engine with
both in-cylinder fuel injection valves for injecting the fuel into
cylinders and port fuel injection valves for injecting the fuel in
an intake port (see, for example, Japanese Patent Laid-Open Gazette
No. 2001-20837). This proposed power output apparatus sets 0 to a
share of fuel injection from the port fuel injection valves in a
stratification range and increases the share of fuel injection from
the port fuel injection valves in a homogeneous range with an
increase in rotation speed of the engine and with an increase in
engine loading. Such control aims to enhance the combustion
performance in the stratification range and to attain the
appropriate combustion performance in the homogeneous range.
SUMMARY OF THE INVENTION
[0006] In the engine with both the in-cylinder fuel injection
valves and the port fuel injection valves, the allocation rate of
fuel injection from the in-cylinder fuel injection valves to fuel
injection from the port fuel injection valves is varied according
to the engine rotation speed and the engine loading. Varying the
allocation rate of fuel injection is expected to enhance the
efficiency and the performances of the engine. A simple variation
in allocation rate of fuel injection, however, does not attain the
sufficient effects on efficiency and performance improvement. The
engine is operable with high efficiency at a high-efficient drive
point, which is one of multiple drive points outputting an
identical power. The high-efficient drive point of the engine
operated with fuel injection from only the in-cylinder fuel
injection valves is often different from the high-efficient drive
point of the engine operated with fuel injection from only the port
fuel injection valves. In the operation of the engine with the
varying allocation rate of fuel injection from the in-cylinder fuel
injection valves to fuel injection from the port fuel injection
valves, the operation efficiency of the engine depends upon the
drive point of the engine. The engine is driven with a change in
drive point among the multiple drive points outputting an identical
power. For example, the engine is driven at the high-efficient
drive point under some conditions and at a high torque drive point
for output of a higher torque under other conditions. In such
cases, it is desirable to determine the optimum drive point of the
engine by taking into account the change in drive point.
[0007] The power output apparatus of the invention, the vehicle
equipped with the power output apparatus, and the control method of
the power output apparatus thus aim to attain efficient operation
of an internal combustion engine with shared fuel injection from
in-cylinder fuel injection valves and from port fuel injection
valves at a specified allocation rate. The power output apparatus
of the invention, the vehicle equipped with the power output
apparatus, and the control method of the power output apparatus
also aim to attain appropriate operation of the internal combustion
engine with shared fuel injection from the in-cylinder fuel
injection valves and from the port fuel injection valves at a
specified allocation rate.
[0008] In order to attain at least part of the above and the other
related objects, the power output apparatus of the invention, the
vehicle equipped with the power output apparatus, and the control
method of the power output apparatus have the configurations
discussed below.
[0009] The present invention is directed to a power output
apparatus that outputs power to a driveshaft. The power output
apparatus including: an internal combustion engine that outputs
power and has an in-cylinder fuel injection valve for injecting a
fuel into a cylinder and a port fuel injection valve for injecting
the fuel in an intake port; a torque conversion unit that converts
the output power of the internal combustion engine by torque
conversion and transmits the converted power to the driveshaft; a
target driving force setting module that sets a target driving
force to be output to the driveshaft; a target power setting module
that sets a target power to be output from the internal combustion
engine, based on the set target driving force; a target operating
state setting module that sets a target operating state of the
internal combustion engine, based on the set target power, a
specified allocation rate of fuel injection from the in-cylinder
fuel injection valve to fuel injection from the port fuel injection
valve, a first constraint, and a second constraint, where the first
constraint is imposed on an operating state of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at a
predetermined first allocation rate, and the second constraint is
imposed on the operating state of the internal combustion engine
with shared fuel injection from the in-cylinder fuel injection
valve and from the port fuel injection valve at a predetermined
second allocation rate different from the first allocation rate;
and a control module that controls the internal combustion engine
and the torque conversion unit to drive the internal combustion
engine in the target operating state with fuel injection at the
specified allocation rate and to ensure output of the target
driving force to the driveshaft.
[0010] The power output apparatus of the invention sets the target
power to be output from the internal combustion engine, based on
the target driving force to be output to the driveshaft. The power
output apparatus subsequently sets the target operating state of
the internal combustion engine, based on the set target power, the
specified allocation rate of fuel injection from the in-cylinder
fuel injection valve to fuel injection from the port fuel injection
valve, the first constraint, and the second constraint. Here the
first constraint is imposed on the operating state of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at the
predetermined first allocation rate. The second constraint is
imposed on the operating state of the internal combustion engine
with shared fuel injection from the in-cylinder fuel injection
valve and from the port fuel injection valve at the predetermined
second allocation rate different from the first allocation rate.
The power output apparatus then controls the internal combustion
engine and the torque conversion unit to drive the internal
combustion engine in the target operating state with fuel injection
at the specified allocation rate and to ensure output of the target
driving force to the driveshaft. Namely the target operating state
of the internal combustion engine is set according to the target
power to be output from the internal combustion engine, the
specified allocation rate of fuel injection from the in-cylinder
fuel injection valve to fuel injection from the port fuel injection
valve, the first constraint imposed on the operating state of the
internal combustion engine at the predetermined first allocation
rate, and the second constraint imposed on the operating state of
the internal combustion engine at the predetermined second
allocation rate. The control of the internal combustion engine and
the torque conversion unit enables operation of the internal
combustion engine in the target operating state and ensures output
of the target driving force to the driveshaft. The internal
combustion engine is driven in the target operating state, which is
set according to the specified allocation rate of fuel injection
from the in-cylinder fuel injection valve to fuel injection from
the port fuel injection valve. This arrangement attains efficient
and appropriate operation of the internal combustion engine with
shared fuel injection from the in-cylinder fuel injection valve and
from the port fuel injection valve at the specified allocation
rate.
[0011] In one preferable embodiment of the power output apparatus
of the invention, the target operating state setting module sets
the target operating state of the internal combustion engine by
distributing a first operating state and a second operating state
of the internal combustion engine by a ratio of the specified
allocation rate to the predetermined first allocation rate and a
ratio of the specified allocation rate to the predetermined second
allocation rate, where the first operating state of the internal
combustion engine is set based on the first constraint and the
target power and the second operating state of the internal
combustion engine is set based on the second constraint and the
target power. In this embodiment, the first operating state and the
second operating state are distributed according to the ratio of
the specified allocation rate to the predetermined first allocation
rate and the ratio of the specified allocation rate to the
predetermined second allocation rate. This arrangement sets an
optimum operating state between the first operating state and the
second operating state to the target operating state and drives the
internal combustion engine in the target operating state. This
attains efficient and appropriate operation of the internal
combustion engine.
[0012] In another preferable embodiment of the power output
apparatus of the invention, each of the first constraint and the
second constraint includes multiple restrictions with regard to
multiple conditions. The target operating state setting module sets
the target operating state of the internal combustion engine, based
on a certain restriction included in the first constraint and a
corresponding restriction included in the second constraint with
regard to a selected condition among the multiple conditions. When
the internal combustion engine is driven with the multiple
restrictions, the arrangement of this embodiment ensures
appropriate operation of the internal combustion engine with the
restrictions under the selected condition. The multiple
restrictions may include at least one of an efficient operation
restriction for efficient operation of the internal combustion
engine and a high torque output restriction for output of a high
torque from the internal combustion engine.
[0013] In still another preferable embodiment of the power output
apparatus of the invention, the first constraint regards operation
of the internal combustion engine with fuel injection from only the
in-cylinder fuel injection valve, and the second constraint regards
operation of the internal combustion engine with fuel injection
from only the port fuel injection valve. The operation of the
internal combustion engine is thus controllable with the
restriction imposed on the operation of the internal combustion
engine with fuel injection from only the in-cylinder fuel injection
valve and with the restriction imposed on the operation of the
internal combustion engine with fuel injection from only the port
fuel injection valve.
[0014] In one preferable embodiment of the power output apparatus
of the invention, the torque conversion unit is a continuously
variable transmission, and the control module varies a change gear
ratio of the torque conversion unit to drive and rotate the
internal combustion engine at a rotation speed specified by the set
target operating state.
[0015] In another preferable embodiment of the power output
apparatus of the invention, the torque conversion unit includes: an
electric power-mechanical power input output mechanism that is
connected to an output shaft of the internal combustion engine and
to the driveshaft and outputs at least part of the output power of
the internal combustion engine to the driveshaft through input and
output of electric power and mechanical power; a motor that inputs
and outputs power from and to the driveshaft; and an accumulator
unit that receives and transmits electric power from and to the
electric power-mechanical power input output mechanism and the
motor. The control module controls the internal combustion engine,
the electric power-mechanical power input output mechanism, and the
motor to drive the internal combustion engine in the target
operating state and to ensure output of a driving force equivalent
to the target driving force to the driveshaft. The electric
power-mechanical power input output mechanism may includes: a three
shaft-type power input output module that is linked to three
shafts, the output shaft of the internal combustion engine, the
driveshaft, and a rotating shaft, and inputs and outputs power from
and to a residual one shaft based on powers input from and output
to any two shafts among the three shafts; and a generator that
inputs and outputs power from and to the rotating shaft.
[0016] The present invention is also directed to a vehicle. The
vehicle comprising: an internal combustion engine that outputs
power and has an in-cylinder fuel injection valve for injecting a
fuel into a cylinder and a port fuel injection valve for injecting
the fuel in an intake port; a torque conversion unit that converts
the output power of the internal combustion engine by torque
conversion and transmits the converted power to the driveshaft
connected to an axle; a target driving force setting module that
sets a target driving force to be output to the driveshaft; a
target power setting module that sets a target power to be output
from the internal combustion engine, based on the set target
driving force; a target operating state setting module that sets a
target operating state of the internal combustion engine, based on
the set target power, a specified allocation rate of fuel injection
from the in-cylinder fuel injection valve to fuel injection from
the port fuel injection valve, a first constraint, and a second
constraint, where the first constraint is imposed on an operating
state of the internal combustion engine with shared fuel injection
from the in-cylinder fuel injection valve and from the port fuel
injection valve at a predetermined first allocation rate, and the
second constraint is imposed on the operating state of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at a
predetermined second allocation rate different from the first
allocation rate; and a control module that controls the internal
combustion engine and the torque conversion unit to drive the
internal combustion engine in the target operating state with fuel
injection at the specified allocation rate and to ensure output of
the target driving force to the driveshaft.
[0017] The vehicle of the invention sets the target power to be
output from the internal combustion engine, based on the target
driving force to be output to the driveshaft. The vehicle
subsequently sets the target operating state of the internal
combustion engine, based on the set target power, the specified
allocation rate of fuel injection from the in-cylinder fuel
injection valve to fuel injection from the port fuel injection
valve, the first constraint, and the second constraint. Here the
first constraint is imposed on the operating state of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at the
predetermined first allocation rate. The second constraint is
imposed on the operating state of the internal combustion engine
with shared fuel injection from the in-cylinder fuel injection
valve and from the port fuel injection valve at the predetermined
second allocation rate different from the first allocation rate.
The vehicle then controls the internal combustion engine and the
torque conversion unit to drive the internal combustion engine in
the target operating state with fuel injection at the specified
allocation rate and to ensure output of the target driving force to
the driveshaft. Namely the target operating state of the internal
combustion engine is set according to the target power to be output
from the internal combustion engine, the specified allocation rate
of fuel injection from the in-cylinder fuel injection valve to fuel
injection from the port fuel injection valve, the first constraint
imposed on the operating state of the internal combustion engine at
the predetermined first allocation rate, and the second constraint
imposed on the operating state of the internal combustion engine at
the predetermined second allocation rate. The control of the
internal combustion engine and the torque conversion unit enables
operation of the internal combustion engine in the target operating
state and ensures output of the target driving force to the
driveshaft. The internal combustion engine is driven in the target
operating state, which is set according to the specified allocation
rate of fuel injection from the in-cylinder fuel injection valve to
fuel injection from the port fuel injection valve. This arrangement
attains efficient and appropriate operation of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at the
specified allocation rate.
[0018] In one preferable embodiment of the vehicle of the
invention, the target operating state setting module sets the
target operating state of the internal combustion engine by
distributing a first operating state and a second operating state
of the internal combustion engine by a ratio of the specified
allocation rate to the predetermined first allocation rate and a
ratio of the specified allocation rate to the predetermined second
allocation rate, where the first operating state of the internal
combustion engine is set based on the first constraint and the
target power and the second operating state of the internal
combustion engine is set based on the second constraint and the
target power. In this embodiment, the first operating state and the
second operating state are distributed according to the ratio of
the specified allocation rate to the predetermined first allocation
rate and the ratio of the specified allocation rate to the
predetermined second allocation rate. This arrangement sets an
optimum operating state between the first operating state and the
second operating state to the target operating state and drives the
internal combustion engine in the target operating state. This
attains efficient and appropriate operation of the internal
combustion engine.
[0019] In another preferable embodiment of the vehicle of the
invention, each of the first constraint and the second constraint
includes multiple restrictions with regard to multiple conditions.
The target operating state setting module sets the target operating
state of the internal combustion engine, based on a certain
restriction included in the first constraint and a corresponding
restriction included in the second constraint with regard to a
selected condition among the multiple conditions. When the internal
combustion engine is driven with the multiple restrictions, the
arrangement of this embodiment ensures appropriate operation of the
internal combustion engine with the restrictions under the selected
condition.
[0020] In still another preferable embodiment of the vehicle of the
invention, the first constraint regards operation of the internal
combustion engine with fuel injection from only the in-cylinder
fuel injection valve, and the second constraint regards operation
of the internal combustion engine with fuel injection from only the
port fuel injection valve. The operation of the internal combustion
engine is thus controllable with the restriction imposed on the
operation of the internal combustion engine with fuel injection
from only the in-cylinder fuel injection valve and with the
restriction imposed on the operation of the internal combustion
engine with fuel injection from only the port fuel injection
valve.
[0021] In one preferable embodiment of the vehicle of the
invention, the torque conversion unit is a continuously variable
transmission, and the control module varies a change gear ratio of
the torque conversion unit to drive and rotate the internal
combustion engine at a rotation speed specified by the set target
operating state.
[0022] In another preferable embodiment of the vehicle of the
invention, the torque conversion unit includes: an electric
power-mechanical power input output mechanism that is connected to
an output shaft of the internal combustion engine and to the
driveshaft and outputs at least part of the output power of the
internal combustion engine to the driveshaft through input and
output of electric power and mechanical power; a motor that inputs
and outputs power from and to the driveshaft; and an accumulator
unit that receives and transmits electric power from and to the
electric power-mechanical power input output mechanism and the
motor. The control module controls the internal combustion engine,
the electric power-mechanical power input output mechanism, and the
motor to drive the internal combustion engine in the target
operating state and to ensure output of a driving force equivalent
to the target driving force to the driveshaft. In this embodiment
of the vehicle of the invention, the electric power-mechanical
power input output mechanism includes: a three shaft-type power
input output module that is linked to three shafts, the output
shaft of the internal combustion engine, the driveshaft, and a
rotating shaft, and inputs and outputs power from and to a residual
one shaft based on powers input from and output to any two shafts
among the three shafts; and a generator that inputs and outputs
power from and to the rotating shaft.
[0023] The present invention is directed to a control method of a
power output apparatus. The power output apparatus including: an
internal combustion engine that outputs power and has an
in-cylinder fuel injection valve for injecting a fuel into a
cylinder and a port fuel injection valve for injecting the fuel in
an intake port; and a torque conversion unit that converts the
output power of the internal combustion engine by torque conversion
and transmits the converted power to a driveshaft. The control
method including the steps of: (a) setting a target driving force
to be output to the driveshaft, and setting a target power to be
output from the internal combustion engine based on the set target
driving force; (b) setting a target operating state of the internal
combustion engine, based on the set target power, a specified
allocation rate of fuel injection from the in-cylinder fuel
injection valve to fuel injection from the port fuel injection
valve, a first constraint, and a second constraint, where the first
constraint is imposed on an operating state of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at a
predetermined first allocation rate, and the second constraint is
imposed on the operating state of the internal combustion engine
with shared fuel injection from the in-cylinder fuel injection
valve and from the port fuel injection valve at a predetermined
second allocation rate different from the first allocation rate;
and (c) controlling the internal combustion engine and the torque
conversion unit to drive the internal combustion engine in the
target operating state with fuel injection at the specified
allocation rate and to ensure output of the target driving force to
the driveshaft.
[0024] The control method of the power output apparatus of the
invention sets the target power to be output from the internal
combustion engine, based on the target driving force to be output
to the driveshaft. The power output apparatus subsequently sets the
target operating state of the internal combustion engine, based on
the set target power, the specified allocation rate of fuel
injection from the in-cylinder fuel injection valve to fuel
injection from the port fuel injection valve, the first constraint,
and the second constraint. Here the first constraint is imposed on
the operating state of the internal combustion engine with shared
fuel injection from the in-cylinder fuel injection valve and from
the port fuel injection valve at the predetermined first allocation
rate. The second constraint is imposed on the operating state of
the internal combustion engine with shared fuel injection from the
in-cylinder fuel injection valve and from the port fuel injection
valve at the predetermined second allocation rate different from
the first allocation rate. The power output apparatus then controls
the internal combustion engine and the torque conversion unit to
drive the internal combustion engine in the target operating state
with fuel injection at the specified allocation rate and to ensure
output of the target driving force to the driveshaft. Namely the
target operating state of the internal combustion engine is set
according to the target power to be output from the internal
combustion engine, the specified allocation rate of fuel injection
from the in-cylinder fuel injection valve to fuel injection from
the port fuel injection valve, the first constraint imposed on the
operating state of the internal combustion engine at the
predetermined first allocation rate, and the second constraint
imposed on the operating state of the internal combustion engine at
the predetermined second allocation rate. The control of the
internal combustion engine and the torque conversion unit enables
operation of the internal combustion engine in the target operating
state and ensures output of the target driving force to the
driveshaft. The internal combustion engine is driven in the target
operating state, which is set according to the specified allocation
rate of fuel injection from the in-cylinder fuel injection valve to
fuel injection from the port fuel injection valve. This arrangement
attains efficient and appropriate operation of the internal
combustion engine with shared fuel injection from the in-cylinder
fuel injection valve and from the port fuel injection valve at the
specified allocation rate.
[0025] In one preferable embodiment of the control method of the
power output apparatus of the invention, the step (b) sets the
target operating state of the internal combustion engine by
distributing a first operating state and a second operating state
of the internal combustion engine by a ratio of the specified
allocation rate to the predetermined first allocation rate and a
ratio of the specified allocation rate to the predetermined second
allocation rate, where the first operating state of the internal
combustion engine is set based on the first constraint and the
target power and the second operating state of the internal
combustion engine is set based on the second constraint and the
target power. In this embodiment, the first operating state and the
second operating state are distributed according to the ratio of
the specified allocation rate to the predetermined first allocation
rate and the ratio of the specified allocation rate to the
predetermined second allocation rate. This arrangement sets an
optimum operating state between the first operating state and the
second operating state to the target operating state and drives the
internal combustion engine in the target operating state. This
attains efficient and appropriate operation of the internal
combustion engine.
[0026] In another preferable embodiment of the control method of
the power output apparatus of the invention, each of the first
constraint and the second constraint includes multiple restrictions
with regard to multiple conditions. The step (b) sets the target
operating state of the internal combustion engine, based on a
certain restriction included in the first constraint and a
corresponding restriction included in the second constraint with
regard to a selected condition among the multiple conditions. When
the internal combustion engine is driven with the multiple
restrictions, the arrangement of this embodiment ensures
appropriate operation of the internal combustion engine with the
restrictions under the selected condition.
[0027] In still another preferable embodiment of the control method
of the power output apparatus of the invention, the first
constraint regards operation of the internal combustion engine with
fuel injection from only the in-cylinder fuel injection valve, and
the second constraint regards operation of the internal combustion
engine with fuel injection from only the port fuel injection valve.
The operation of the internal combustion engine is thus
controllable with the restriction imposed on the operation of the
internal combustion engine with fuel injection from only the
in-cylinder fuel injection valve and with the restriction imposed
on the operation of the internal combustion engine with fuel
injection from only the port fuel injection valve.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 schematically illustrates the configuration of a
hybrid vehicle equipped with a power output apparatus in one
embodiment of the invention;
[0029] FIG. 2 schematically shows the structure of an engine
mounted on the hybrid vehicle of the embodiment;
[0030] FIG. 3 is a drive control routine executed by a hybrid
electronic control unit included in the hybrid vehicle of the
embodiment;
[0031] FIG. 4 shows one example of a torque demand setting map;
[0032] FIG. 5 shows a fuel consumption-priority operation curve and
a high torque operation curve for in-cylinder injection to set a
rotation speed Ni and a torque Ti for in-cylinder injection;
[0033] FIG. 6 shows a fuel consumption-priority operation curve and
a high torque operation curve for port injection to set a rotation
speed Np and a torque Tp for port injection;
[0034] FIG. 7 is an alignment chart showing torque-rotation speed
dynamics of respective rotational elements of a power distribution
integration mechanism included in the hybrid vehicle of the
embodiment;
[0035] FIG. 8 schematically illustrates the configuration of
another hybrid vehicle in one modified example;
[0036] FIG. 9 schematically illustrates the configuration of still
another hybrid vehicle in another modified example;
[0037] FIG. 10 schematically illustrates the configuration of a
motor vehicle equipped with a power output apparatus in a second
embodiment of the invention; and
[0038] FIG. 11 is a flowchart showing a drive control routine
executed by an electronic control unit included in the motor
vehicle of the second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] One mode of carrying out the invention is described below as
a preferred embodiment. FIG. 1 schematically illustrates the
configuration of a hybrid vehicle 20 equipped with a power output
apparatus in one embodiment of the invention. As illustrated, the
hybrid vehicle 20 of the embodiment includes an engine 22 and a
three shaft-type power distribution integration mechanism 30 having
a sun gear 31, a ring gear 32, and a carrier 34 connecting with
multiple pinion gears 33. The carrier 34 of the power distribution
integration mechanism 30 is linked to a crankshaft 26 or an output
shaft of the engine 22 via a damper 28. A ring gear shaft 32a
connecting with the ring gear 32 is linked to drive wheels 39a and
39b via a gear mechanism 37 and a differential gear 38. The hybrid
vehicle 20 of the embodiment further includes a motor MG1 that is
linked to the sun gear 31 of the power distribution integration
mechanism 30 and has power generation capability, a motor MG2 that
is linked to the ring gear 32 of the power distribution integration
mechanism 30 via the ring gear shaft 32a and a reduction gear 35,
and a hybrid electronic control unit 70 that controls the
operations of the whole power output apparatus.
[0040] As illustrated in FIG. 2, the engine 22 is constructed as an
internal combustion engine having multiple in-cylinder fuel
injection valves 125 (125a through 125d in FIG. 1) for directly
injecting a hydrocarbon fuel, such as gasoline or light oil, into
cylinders and multiple port fuel injection valves 126 (126a through
126d in FIG. 1) for injecting the fuel in an intake port. The
engine 22 having the two sets of the fuel injection valves 125 and
126 are operated and controlled in one of a port injection drive
mode, an in-cylinder injection drive mode, and in a shared
injection drive mode. In the port injection drive mode, the air
cleaned by an air cleaner 122 and taken in via a throttle valve 124
is mixed with the atomized fuel injected from the port fuel
injection valves 126 to the air-fuel mixture. The air-fuel mixture
is introduced into a combustion chamber of each cylinder by an
intake valve 128 and is ignited with a spark of an ignition plug
130 to be explosively combusted. The reciprocating motions of a
piston 132 in each cylinder by the combustion energy are converted
into rotational motions of the crankshaft 26. In the in-cylinder
injection drive mode, while the air cleaned by the air cleaner 122
and taken in via the throttle valve 124 is introduced into the
combustion chamber of each cylinder by the intake valve 128, the
fuel is injected from the in-cylinder fuel injection valves 125 in
the course of an intake stroke or in a compression stroke in the
cylinder. The resulting air-fuel mixture is ignited with the spark
of the ignition plug 130 to be explosively combusted and give the
rotational motions of the crankshaft 26. In the shared injection
drive mode, the air is mixed with the fuel injected from the port
fuel injection valves 126 and is introduced as the air-fuel mixture
into the combustion chamber, while the air in the combustion
chamber is mixed with the fuel injected from the in-cylinder fuel
injection valves 125 in the intake stroke or in the compression
stroke. Combustion of the resulting air-fuel mixture gives the
rotational motions of the crankshaft 26. The operation mode of the
engine 22 is selectively changed over among these three drive modes
according to the actual operating conditions and required operating
conditions of the engine 22. The exhaust from the engine 22 goes
through a catalytic converter (three-way catalyst) 134 that
converts toxic components included in the exhaust, that is, carbon
monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx), into
harmless components, and is discharged to the outside air.
[0041] As shown in FIG. 1, the port fuel injection valves 126a
through 126d receive a supply of fuel fed from a fuel tank 60 by
means of a fuel pump 62. The in-cylinder fuel injection valves 125a
through 125d receive a high-pressure supply of fuel fed from the
fuel tank 60 by means of the fuel pump 62, pressurized by a
high-pressure fuel pump 64, and delivered through a delivery pipe
66. Motors 62a and 64a working as actuators of the fuel pump 62 and
the high-pressure fuel pump 64 receive a supply of electric power
from a battery 50 via a DC-DC converter 90. A check valve (not
shown) is provided on a discharge side of the high-pressure fuel
pump 64 to prevent a reverse flow of the fuel and to keep a fuel
pressure in the delivery pipe 66 at a constant level. The delivery
pipe 66 is connected with a relief pipe 68 that circulates the flow
of fuel into the fuel tank 60 via a relief valve 67 for preventing
an excessive level of the fuel pressure. The fuel pressure of the
fuel supplied to the in-cylinder fuel injection valves 125a through
125d in a stop state of the engine 22 is decreased to a preset
level to prevent leakage of the fuel from the in-cylinder fuel
injection valves 125a through 125d.
[0042] The engine 22 is under control of an engine electronic
control unit 24 (hereafter referred to as engine ECU 24). The
engine ECU 24 receives, via its input port (not shown), diverse
signals from various sensors that measure and detect the operating
conditions of the engine 22. The signals input into the engine ECU
24 include a crank position from a crank position sensor 140
detected as the rotational position of the crankshaft 26, a cooling
water temperature from a water temperature sensor 142 measured as
the temperature of cooling water in the engine 22, a cam position
from a cam position sensor 144 detected as the rotational position
of a camshaft driven to open and close the intake valve 128 and an
exhaust valve for gas intake and exhaust into and from the
combustion chambers, a throttle valve position from a throttle
valve position sensor 146 detected as the opening or position of
the throttle valve 124, an intake air flow from a vacuum sensor 148
measured as the load of the engine 22, and a fuel pressure Pf from
a fuel pressure sensor 69 attached to the delivery pipe 66 for
supplying the fuel to the in-cylinder fuel injection valves 125a
through 125d. The engine ECU 24 outputs, via its output port (not
shown), diverse control signals and driving signals to drive and
control the engine 22. The signals output from the engine ECU 24
include driving signals to the in-cylinder fuel injection valves
125a through 125d and the port fuel injection valves 126a through
126d, driving signals to a throttle valve motor 136 for regulating
the position of the throttle valve 124, control signals to an
ignition coil 138 integrated with an igniter, control signals to a
variable valve timing mechanism 150 to vary the open and close
timings of the intake valve 128, and driving signals to the motors
62a and 64a of the fuel pump 62 and the high-pressure fuel pump 64.
The engine ECU 24 establishes communication with the hybrid
electronic control unit 70 to drive and control the engine 22 in
response to control signals received from the hybrid electronic
control unit 70 and to output data regarding the operating
conditions of the engine 22 to the hybrid electronic control unit
70 according to the requirements.
[0043] The motors MG1 and MG2 are constructed as known synchronous
motor generators that may be actuated both as a generator and as a
motor. The motors MG1 and MG2 are connected with the battery 50 by
power lines 54 and transmit electric powers to and from the battery
50 via inverters 41 and 42. Both the motors MG1 and MG2 are driven
and controlled by a motor electronic control unit 40 (hereafter
referred to as motor ECU 40). The motor ECU 40 inputs signals
required for controlling the operations of the motors MG1 and MG2,
for example, signals representing rotational positions of rotors in
the motors MG1 and MG2 from rotational position detection sensors
43 and 44 and signals representing phase currents to be applied to
the motors MG1 and MG2 from electric current sensors (not shown).
The motor ECU 40 outputs switching control signals to the inverters
41 and 42. The motor ECU40 establishes communication with the
hybrid electronic control unit 70 to drive and control the motors
MG1 and MG2 in response to control signals received from the hybrid
electronic control unit 70 and to output data regarding the
operating conditions of the motors MG1 and MG2 to the hybrid
electronic control unit 70 according to the requirements.
[0044] The battery 50 is under control of a battery electronic
control unit (hereafter referred to as battery ECU) 52. The battery
ECU 52 receives diverse signals required for control of the battery
50, for example, an inter-terminal voltage measured by a voltage
sensor (not shown) disposed between terminals of the battery 50, a
charge-discharge current measured by a current sensor (not shown)
attached to the power line 54 connected with the output terminal of
the battery 50, and a battery temperature Tb measured by a
temperature sensor 51 attached to the battery 50. The battery ECU
52 outputs data relating to the state of the battery 50 to the
hybrid electronic control unit 70 via communication according to
the requirements. The battery ECU 52 calculates a state of charge
(SOC) of the battery 50, based on the accumulated charge-discharge
current measured by the current sensor, for control of the battery
50.
[0045] The hybrid electronic control unit 70 is constructed as a
microprocessor including a CPU 72, a ROM 74 that stores processing
programs, a RAM 76 that temporarily stores data, and a
non-illustrated input-output port, and a non-illustrated
communication port. The hybrid electronic control unit 70 receives
various inputs via the input port: an ignition signal from an
ignition switch 80, a gearshift position SP from a gearshift
position sensor 82 that detects the current position of a gearshift
lever 81, an accelerator opening Acc from an accelerator pedal
position sensor 84 that measures a step-on amount of an accelerator
pedal 83, a brake pedal position BP from a brake pedal position
sensor 86 that measures a step-on amount of a brake pedal 85, and a
vehicle speed V from a vehicle speed sensor 88. The hybrid
electronic control unit 70 communicates with the engine ECU 24, the
motor ECU 40, and the battery ECU 52 via the communication port to
transmit diverse control signals and data to and from the engine
ECU 24, the motor ECU 40, and the battery ECU 52, as mentioned
previously.
[0046] The hybrid vehicle 20 of the embodiment thus constructed
calculates a torque demand Tr* to be output to the ring gear shaft
32a functioning as the drive shaft, based on observed values of a
vehicle speed V and an accelerator opening Acc, which corresponds
to a driver's step-on amount of an accelerator pedal 83. The engine
22 and the motors MG1 and MG2 are subjected to operation control to
output a required level of power corresponding to the calculated
torque demand Tr* to the ring gear shaft 32a. The operation control
of the engine 22 and the motors MG1 and MG2 selectively effectuates
one of a torque conversion drive mode, a charge-discharge drive
mode, and a motor drive mode. The torque conversion drive mode
controls the operations of the engine 22 to output a quantity of
power equivalent to the required level of power, while driving and
controlling the motors MG1 and MG2 to cause all the power output
from the engine 22 to be subjected to torque conversion by means of
the power distribution integration mechanism 30 and the motors MG1
and MG2 and output to the ring gear shaft 32a. The charge-discharge
drive mode controls the operations of the engine 22 to output a
quantity of power equivalent to the sum of the required level of
power and a quantity of electric power consumed by charging the
battery 50 or supplied by discharging the battery 50, while driving
and controlling the motors MG1 and MG2 to cause all or part of the
power output from the engine 22 equivalent to the required level of
power to be subjected to torque conversion by means of the power
distribution integration mechanism 30 and the motors MG1 and MG2
and output to the ring gear shaft 32a, simultaneously with charge
or discharge of the battery 50. The motor drive mode stops the
operations of the engine 22 and drives and controls the motor MG2
to output a quantity of power equivalent to the required level of
power to the ring gear shaft 32a. The torque conversion drive mode
is equivalent to the charge-discharge drive mode with the
charge-discharge electric power of the battery 50 equal to zero.
There is accordingly no necessity to specifically discriminate the
torque conversion drive mode from the charge-discharge drive mode.
The hybrid vehicle 20 of the embodiment thus runs with changeover
of the drive mode between the motor drive mode and the
charge-discharge drive mode.
[0047] The description regards the operations of the hybrid vehicle
20 of the embodiment having the configuration discussed above. FIG.
3 is a flowchart showing a drive control routine executed by the
hybrid electronic control unit 70 in the hybrid vehicle 20 of the
embodiment. This drive control routine is performed repeatedly at
preset time intervals, for example, at every several msec.
[0048] In the drive control routine of FIG. 3, the CPU 72 of the
hybrid electronic control unit 70 first inputs various data
required for control, that is, the accelerator opening Acc from the
accelerator pedal position sensor 84, the vehicle speed V from the
vehicle speed sensor 88, rotation speeds Nm1 and Nm2 of the motors
MG1 and MG2, the state of charge SOC of the battery 50, an input
limit Win and an output limit Wout of the battery 50, an allocation
rate k of fuel injection from the in-cylinder fuel injection valves
125 to fuel injection from the port fuel injection valves 126, and
a high torque request with preference to a high torque over fuel
consumption (step S100). The rotation speeds Nm1 and Nm2 of the
motors MG1 and MG2 are computed from the rotational positions of
the respective rotors in the motors MG1 and MG2 detected by the
rotational position detection sensors 43 and 44 and are received
from the motor ECU 40 by communication. The state of charge SOC of
the battery 50 is computed from the accumulated charge-discharge
current of the battery 50 measured by the electric current sensor
(not shown) and is received from the battery ECU 52 by
communication. The input limit Win and the output limit Wout of the
battery 50 are set based on the battery temperature and the state
of charge SOC of the battery 50 and are received from the battery
ECU 52 by communication. The allocation rate k is set according to
an allocation rate setting routine (not shown) executed by the
hybrid electronic control unit 70. The high torque request is
entered corresponding to the value of a flag that selectively
specifies either a fuel consumption priority or a torque priority
based on the driver's depression amount and the depression speed of
the accelerator pedal 83.
[0049] After the data input, the CPU 72 sets a torque demand Tr* to
be output to the ring gear shaft 32a or a driveshaft linked with
the drive wheels 39a and 39b and a vehicle power demand Pe*
required for the whole hybrid vehicle 20, based on the input
accelerator opening Acc and the input vehicle speed V (step S110).
A concrete procedure of setting the torque demand Tr* in this
embodiment stores in advance variations in torque demand Tr*
against the accelerator opening Acc and the vehicle speed V as a
torque demand setting map in the ROM 74 and reads the torque demand
Tr* corresponding to the given accelerator opening Acc and the
given vehicle speed V from this torque demand setting map. One
example of the torque demand setting map is shown in FIG. 4. The
vehicle power demand Pe* is calculated as the sum of the product of
the torque demand Tr* and a rotation speed Nr of the ring gear
shaft 32a, a charge-discharge power demand Pb* to be charged into
or discharged from the battery 50, and a potential loss. The
rotation speed Nr of the ring gear shaft 32a is obtained by
dividing the rotation speed Nm2 of the motor MG2 by a gear ratio Gr
of the reduction gear 35 or by multiplying the vehicle speed V by a
preset conversion factor. The charge-discharge electric power Pb*
is set based on the state of charge SOC of the battery 50 and the
accelerator opening Acc.
[0050] The CPU 72 subsequently specifies the presence or the
absence of the high torque request (step S120). In the absence of
the high torque request (step S120: No), fuel consumption-priority
operation curves as constraints for efficient operation of the
engine 22 are set to working operation curves used as constraints
to set the drive point of the engine 22 (step S130). In the
presence of the high torque request (step S120: Yes), on the other
hand, high torque operation curves as constraints for output of a
higher torque from the engine 22 at a fixed rotation speed are set
to the working operation curves (step S140). FIG. 5 shows one
example of the fuel consumption-priority operation curve and the
high torque operation curve used in the operation of the engine 22
with fuel injection from only the in-cylinder fuel injection valves
125. FIG. 6 shows one example of the fuel consumption-priority
operation curve and the high torque operation curve used in the
operation of the engine 22 with fuel injection from only the port
fuel injection valves 126. The one-dot chain line curve in FIG. 5
shows the fuel consumption-priority operation curve used in the
operation of the engine 22 with fuel injection from only the port
fuel injection valves 126. The one-dot chain line curve in FIG. 6
shows the high torque operation curve used in the operation of the
engine 22 with fuel injection from only the in-cylinder fuel
injection valves 125. As clearly understood from FIGS. 5 and 6, the
high torque operation curve is located at the higher torque than
the fuel consumption-priority operation curve. The in-cylinder
injection gives the higher filling rate of the intake air into the
combustion chamber than the port injection. Both the fuel
consumption-priority operation curve and the high torque operation
curve used in the operation of the engine 22 with fuel injection
from only the in-cylinder fuel injection valves 125 are accordingly
located at the higher torque than the fuel consumption-priority
operation curve and the high torque operation curve used in the
operation of the engine 22 with fuel injection from only the port
fuel injection valves 126. Setting the fuel consumption-priority
operation curves to the working operation curves at step S130
respectively sets the fuel consumption-priority operation curve for
in-cylinder injection in the operation of the engine 22 with fuel
injection from only the in-cylinder fuel injection valves 125 and
the fuel consumption-priority operation curve for port injection in
the operation of the engine 22 with fuel injection from only the
port fuel injection valves 126 to the working operation curves.
Setting the high torque operation curves to the working operation
curves at step S140 respectively sets the high torque operation
curve for in-cylinder injection in the operation of the engine 22
with fuel injection from only the in-cylinder fuel injection valves
125 and the high torque operation curve for port injection in the
operation of the engine 22 with fuel injection from only the port
fuel injection valves 126 to the working operation curves.
[0051] The CPU 72 sequentially sets a rotation speed Ni and a
torque Ti for in-cylinder injection as a drive point for outputting
the vehicle power demand Pe* according to the working operation
curves set for in-cylinder injection (step S150) and sets a
rotation speed Np and a torque Tp for port injection as a drive
point for outputting the vehicle power demand Pe* according to the
working operation curves set for port injection (step S160). FIGS.
5 and 6 respectively show a process of setting the rotation speed
Ni and the torque Ti for in-cylinder injection and a process of
setting the rotation speed Np and the torque Tp for port injection,
when the fuel consumption-priority operation curves are set to the
working operation curves for in-cylinder injection and for port
injection. As shown in FIG. 5, the rotation speed Ni and the torque
Ti for in-cylinder injection are given as an intersection of the
fuel consumption-priority operation curve and a curve of constant
vehicle power demand Pe* (=Ni.times.Ti). As shown in FIG. 6, the
rotation speed Np and the torque Tp for port injection are given as
an intersection of the fuel consumption-priority operation curve
and the curve of constant vehicle power demand Pe*
(=Np.times.Tp).
[0052] The CPU 72 sets a target rotation speed Ne* of the engine 22
as distribution of the rotation speed Ni for in-cylinder injection
and the rotation speed Np for port injection by the allocation rate
k according to Equation (1) given below, and divides the vehicle
power demand Pe* by the target rotation speed Ne* to set a target
torque Te* of the engine 22 (step S170) Ne*=kNi+(1-k)Np (1)
[0053] After setting the target rotation speed Ne* and the target
torque Te* of the engine 22, the CPU 72 calculates a target
rotation speed Nm1* of the motor MG1 from the target rotation speed
Ne* of the engine 22, the rotation speed Nr (=Nm2/Gr) of the ring
gear shaft 32a, and a gear ratio .rho. of the power distribution
integration mechanism 30 according to Equation (2) given below,
while calculating a torque command Tm1* of the motor MG1 from the
calculated target rotation speed Nm1* and the current rotation
speed Nm1 of the motor MG1 according to Equation (3) given below
(step S180): Nm1*=(Ne*(1+.rho.)-Nm2/Gr)/.rho. (2) Tm1*=Previous
Tm1*+KP(Nm1*-Nm1)+KI.intg.(Nm1*-Nm1)dt (3) FIG. 7 is an alignment
chart showing torque-rotation speed dynamics of the respective
rotational elements included in the power distribution integration
mechanism 30. The left axis `S`, the middle axis `C`, and the right
axis `R` respectively show the rotation speed of the sun gear 31,
the rotation speed of the carrier 34, and the rotation speed Nr of
the ring gear 32 (ring gear shaft 32a). As mentioned previously,
the rotation speed of the sun gear 31 is equivalent to the rotation
speed Nm1 of the motor MG1, and the rotation speed of the carrier
34 is equivalent to the rotation speed Ne of the engine 22. The
target rotation speed Nm1* of the motor MG1 is thus computable from
the rotation speed Nr of the ring gear shaft 32a, the target
rotation speed Ne* of the engine 22, and the gear ratio .rho. of
the power distribution integration mechanism 30 according to
Equation (2) given above. The torque command Tm1* is then set to
drive and rotate the motor MG1 at the target rotation speed Nm1*.
Drive control of the motor MG1 with the settings of the torque
command Tm1* and the target rotation speed Nm1* enables rotation of
the engine 22 at the target rotation speed Ne*. Equation (3) is a
relational expression of feedback control to drive and rotate the
motor MG1 at the target rotation speed Nm1*. In Equation (3) given
above, `KP` in the second term and `KI` in the third term on the
right side respectively denote a gain of the proportional and a
gain of the integral term. Two upward thick arrows on the axis `R`
in FIG. 7 respectively show a torque that is transmitted to the
ring gear shaft 32a when the torque Te* is output from the engine
22 that is in steady operation at a specific drive point of the
target rotation speed Ne* and the target torque Te*, and a torque
that is applied to the ring gear shaft 32a via the reduction gear
35 when a torque Tm2* is output from the motor MG2.
[0054] After calculation of the target rotation speed Nm1* and the
torque command Tm1* of the motor MG1, the CPU 72 calculates a
tentative motor torque Tm2tmp, which is to be output from the motor
MG2 for application of the torque demand Tr* to the ring gear shaft
32a, from the torque demand Tr*, the torque command Tm1* of the
motor MG1, the gear ratio .rho. of the power distribution
integration mechanism 30, and the gear ratio Gr of the reduction
gear 35 according to Equation (4) given below (step S190):
Tm2tmp=(Tr*+Tm1*/.rho.)/Gr (4) Equation (4) is readily introduced
from the torque balance in the alignment chart of FIG. 7. The CPU
72 then calculates a lower torque restriction Tm2 min and an upper
torque restriction Tm2max as minimum and maximum torques output
from the motor MG2, from the input limit Win and the output limit
Wout of the battery 50, the torque command Tm1* and the current
rotation speed Nm1 of the motor MG1 and the current rotation speed
Nm2 of the motor MG2 according to Equations (5) and (6) given below
(step S200): Tm2min=(Win-Tm1*Nm1)/Nm2 (5)
Tm2max=(Wout-Tm1*-Nm1)/Nm2 (6) The CPU 72 compares the calculated
lower torque restriction Tm2min with the smaller between the
calculated tentative motor torque Tm2tmp and the calculated upper
torque restriction Tm2max and sets the greater to a torque command
Tm2* of the motor MG2 (step S210). Such setting restricts the
torque command Tm2* of the motor MG2 within the range between the
input limit Win and the output limit Wout of the battery 50.
[0055] After setting the target rotation speed Ne* and the target
torque Te* of the engine 22 and the torque commands Tm1* and Tm2*
of the motors MG1 and MG2, the CPU 72 sends the target torque Te*
of the engine 22 and the allocation rate k to the engine ECU 24,
while sending the torque commands Tm1* and Tm2* of the motors MG1
and MG2 to the motor ECU 40 (step S220). The CPU 72 then exits from
this drive control routine of FIG. 3. The engine ECU 24 receives
the target torque Te* and the allocation rate k and performs
required controls and regulations including fuel injection control,
ignition control, and throttle opening regulation. The engine ECU
24 controls fuel injection from the in-cylinder fuel injection
valves 125 and from the port fuel injection valves 126 according to
the allocation rate k and thus enables the engine 22 rotating at
the target rotation speed Ne* to output the target torque Te*. The
motor ECU 40 receives the torque commands Tm1* and Tm2* and
performs switching control of the switching elements included in
the respective inverters 41 and 42 to drive the motor MG1 with the
torque command Tm1* and the motor MG2 with the torque command
Tm2*.
[0056] As described above, in the hybrid vehicle 20 of the
embodiment, the drive control sets the target rotation speed Ne*
and the target torque Te* of the engine 22 by distributing the
rotation speed Ni for in-cylinder injection and the rotation speed
Np for port injection by the allocation rate k of fuel injection
from the in-cylinder fuel injection valves 125 to fuel injection
from the port fuel injection valves 126. Here the rotation speed Ni
for in-cylinder injection is set according to the operation curve
for in-cylinder injection in the operation of the engine 22 with
fuel injection from only the in-cylinder fuel injection valves 125.
The rotation speed Np for port injection is set according to the
operation curve for port injection in the operation of the engine
22 with fuel injection from only the port fuel injection valves
126. The drive control of the hybrid vehicle 20 then sets the
torque commands Tm1* and Tm2* of the motors MG1 and MG2 and
controls the engine 22 and the motors MG1 and MG2 to drive the
engine 22 at a specific drive point defined by the target rotation
speed Ne* and the target torque Te* and to ensure output of the
torque demand Tr* to the ring gear shaft 32a or the driveshaft.
This arrangement enables the engine 22 to be driven in the
appropriate operating conditions and ensures output of the torque
demand Tr* to the ring gear shaft 32a even in the state of shared
fuel injection from the in-cylinder fuel injection valves 125 and
from the port fuel injection valves 126. When the fuel
consumption-priority operation curves are set to the working
operation curves, this arrangement enables efficient operation of
the engine 22 and ensures output of the torque demand Tr* to the
ring gear shaft 32a even in the state of shared fuel injection from
the in-cylinder fuel injection valves 125 and from the port fuel
injection valves 126.
[0057] In the absence of the high torque request, the hybrid
vehicle 20 of the embodiment sets the fuel consumption-priority
operation curves to both the working operation curve for
in-cylinder injection and the working operation curve for port
injection, sets the target rotation speed Ne* and the target torque
Te* of the engine 22 according to the fuel consumption-priority
operation curves, and controls the engine 22 and the motors MG1 and
MG2. In the presence of the high torque request, on the other hand,
the hybrid vehicle 20 of the embodiment sets the high torque
operation curves to both the working operation curve for
in-cylinder injection and the working operation curve for port
injection, sets the target rotation speed Ne* and the target torque
Te* of the engine 22 according to the high torque operation curves,
and controls the engine 22 and the motors MG1 and MG2. This
arrangement enables the engine 22 to be driven in the appropriate
operating conditions and ensures output of the torque demand Tr* to
the ring gear shaft 32a even in the state of shared fuel injection
from the in-cylinder fuel injection valves 125 and from the port
fuel injection valves 126 with a change of the constraint to set
the drive point of the engine 22 in response to the high torque
request.
[0058] In the hybrid vehicle 20 of the embodiment, the operation of
the motor MG2 is controlled with the torque command Tm2*, which is
set within the range of the input limit Win to the output limit
Wout of the battery 50. This arrangement protects the battery 50
from being overcharged with excessive electric power or from being
over-discharged to output excessive electric power, thus preventing
untimely deterioration of the battery 50.
[0059] In the hybrid vehicle 20 of the embodiment, the power of the
engine 22 is output via the power distribution integration
mechanism 30 to the ring gear shaft 32a or the driveshaft connected
to the drive wheels 39a and 39b. The technique of the invention is,
however, not restricted to this configuration but may also be
applicable to another hybrid vehicle 120 of one modified
configuration shown in FIG. 8 or to still another hybrid vehicle
220 of another modified configuration shown in FIG. 9. In the
hybrid vehicle 120 of FIG. 8, the power of the motor MG2 is
transmitted to a different axle (an axle linked to wheels 39c and
39d) from the axle connecting with the ring gear shaft 32a (the
axle linked to the drive wheels 39a and 39b). The hybrid vehicle
220 of FIG. 9 has a pair-rotor motor 230 including an inner rotor
232 connected to the crankshaft 26 of the engine 22 and an outer
rotor 234 connected to a driveshaft for output of the power to the
drive wheels 39a and 39b. The pair-rotor motor 230 transmits part
of the output power of the engine 22 to the driveshaft, while
converting the residual engine output power into electric
power.
[0060] The technique of the invention is also actualized by a motor
vehicle 320 described below as a second embodiment of the
invention. FIG. 10 schematically illustrates the configuration of
the motor vehicle 320 equipped with a power output apparatus in the
second embodiment of the invention. As clearly understood from
comparison between FIG. 1 and FIG. 10, the motor vehicle 320 of the
second embodiment has a torque converter 340 and a belt continuous
variable transmission (CVT) 350, in place of the power distribution
integration mechanism 30 and the motors MG1 and MG2 included in the
hybrid vehicle 20 of the first embodiment. The like constituents in
the motor vehicle 320 of the second embodiment to those in the
hybrid vehicle 20 of the first embodiment are expressed by the like
numerals and symbols and are not specifically described here. In
the motor vehicle 320 of the second embodiment, a battery 330
receives a supply of electric power generated by an alternator (not
shown) actuated via a belt (not shown) set on the crankshaft 26 of
the engine 22 and supplies electric power to the motors 62a and 64a
working as the actuators for the fuel pump 62 and the high-pressure
fuel pump 64.
[0061] As shown in FIG. 10, the motor vehicle 320 of the second
embodiment includes the engine 22 with the in-cylinder fuel
injection valves 125 and the port fuel injection valves 126, which
is identical with the engine 22 included in the hybrid vehicle 20
of the first embodiment. The motor vehicle 320 of the second
embodiment also includes the conventional fluid torque converter
340 connecting with the crankshaft 26 of the engine 22 via the
damper 28, the belt continuous variable transmission (CVT) 350
having an input shaft 351 linked to the torque converter 340 and an
output shaft 352 linked to the gear mechanism 37, which connects
with the drive wheels 39a and 39b via the differential gear 38, and
an electronic control unit 370 controlling the operations of the
whole motor vehicle 320.
[0062] The CVT 350 includes a primary pulley 353 that has a
variable groove width and is linked to the input shaft 351, a
secondary pulley 354 that has a variable groove width and is linked
to the output shaft 352 or a driveshaft, a belt 355 that is set in
the grooves of the primary pulley 353 and the secondary pulley 354,
and first and second actuators 356 and 357 that respectively vary
the groove widths of the primary pulley 353 and the secondary
pulley 354. Varying the groove widths of the primary pulley 353 and
the secondary pulley 354 by the first actuator 356 and the second
actuator 357 attains the continuously variable speed to convert the
power of the input shaft 351 and output the converted power to the
output shaft 352. The first actuator 356 is constructed as a
hydraulic actuator and is used to regulate the change gear ratio.
The second actuator 357 is also constructed as a hydraulic actuator
and is used to adjust the clamping pressure of the belt 355 for
regulation of a torque transmission capacity of the CVT 350. The
hydraulic pressures required for actuation of the first actuator
356 and the second actuator 357 are generated by a mechanical pump
(not shown) attached to the crankshaft 26 of the engine 22. A CVT
electronic control unit 359 (hereafter referred to as CVTECU 359)
takes charge of the variable speed control and the belt clamping
pressure adjustment of the CVT 350. The CVTECU 359 receives a
rotation speed Nin of the input shaft 351 from a rotation speed
sensor 361 attached to the input shaft 351 and a rotation speed
Nout of the output shaft 352 from a rotation speed sensor 362
attached to the output shaft 352. The CVTECU 359 outputs driving
signals to the first actuator 356 and to the second actuator 357.
The CVTECU 359 communicates with the electronic control unit 370.
The CVTECU 359 receives control signals from the electronic control
unit 370 to regulate the change gear ratio (gear ratio .gamma.) of
the CVT 350 and to output data regarding the operating conditions
of the CVT 350, for example, the rotation speed Nin of the input
shaft 351 and the rotation speed Nout of the output shaft 352, to
the electronic control unit 370 according to the requirements.
[0063] Like the hybrid electronic control unit 70 of the first
embodiment, the electronic control unit 370 of the second
embodiment is constructed as a microprocessor including a CPU 372,
a ROM 374 that stores processing programs, a RAM 376 that
temporarily stores data, input and output ports (not shown), and a
communication port (not shown). The electronic control unit 370
receives, via its input port, the ignition signal from the ignition
switch 80, the gearshift position SP or the current setting
position of the gearshift lever 81 from the gearshift position
sensor 82, the accelerator opening Acc or the driver's depression
amount of the accelerator pedal 83 from the accelerator pedal
position sensor 84, the brake pedal position BP or the driver's
depression amount of the brake pedal 85 from the brake pedal
position sensor 86, and the vehicle speed V from the vehicle speed
sensor 88. The electronic control unit 370 is connected with the
engine ECU 24 and the CVTECU 359 via its communication port to
receive and send various data and control signals from and to the
engine ECU 24 and the CVTECU 359.
[0064] The description regards the operations of the motor vehicle
320 of the second embodiment having the configuration discussed
above. FIG. 11 is a flowchart showing a drive control routine
executed by the electronic control unit 370 in the motor vehicle
320 of the second embodiment. This drive control routine is
performed repeatedly at preset time intervals, for example, at
every several msec.
[0065] In the drive control routine of FIG. 11, the CPU 372 of the
electronic control unit 370 first inputs various data required for
control, that is, the accelerator opening Acc from the accelerator
pedal position sensor 84, the vehicle speed V from the vehicle
speed sensor 88, the rotation speed Nin of the input shaft 351, the
rotation speed Nout of the output shaft 352, the allocation rate k
of fuel injection from the in-cylinder fuel injection valves 125 to
fuel injection from the port fuel injection valves 126, and the
high torque request with preference to a high torque over fuel
consumption (step S300). The rotation speed Nin of the input shaft
351 and the rotation speed Nout of the output shaft 352 are
measured respectively by the rotation speed sensors 361 and 362 and
are received from the CVTECU 359 by communication. The allocation
rate k and the high torque request have been defined in the first
embodiment.
[0066] After the data input, the CPU 372 sets a torque demand Tout*
to be output to the output shaft 352 or the driveshaft linked with
the drive wheels 39a and 39b and a vehicle power demand Pe*
required for the whole motor vehicle 320, based on the input
accelerator opening Acc and the input vehicle speed V (step S310).
A concrete procedure of setting the torque demand Tout* in this
embodiment stores in advance variations in torque demand Tout*
against the accelerator opening Acc and the vehicle speed V as a
torque demand setting map in the ROM 374 and reads the torque
demand Tout* corresponding to the given accelerator opening Acc and
the given vehicle speed V from this torque demand setting map. The
torque demand setting map used in the second embodiment is similar
to the map shown in FIG. 4. The vehicle power demand Pe* is
obtained as the product of the torque demand Tout* and the rotation
speed Nout of the output shaft 352.
[0067] The CPU 372 subsequently executes the processing of steps
S320 through S370 to set the target rotation speed Ne* and the
target torque Te* of the engine 22. The processing of steps S320
through S370 is identical with the processing of steps S120 to S170
in the drive control routine of FIG. 3 and is thus not specifically
described here. The CPU 72 then sets the target rotation speed Ne*
of the engine 22 to a target rotation speed Nin* of the input shaft
351 (step S380) and sends the target torque Te* of the engine 22
and the allocation rate k to the engine ECU 24 and the target
rotation speed Ni* of the input shaft 351 to the CVTECU 359 (step
S390). The CPU 72 then exits from this drive control routine of
FIG. 11. As described in the first embodiment, the engine ECU 24
receives the target torque Te* and the allocation rate k and
performs required controls and regulations including fuel injection
control, ignition control, and throttle opening regulation. The
engine ECU 24 controls fuel injection from the in-cylinder fuel
injection valves 125 and from the port fuel injection valves 126
according to the allocation rate k and thus enables the engine 22
rotating at the target rotation speed Ne* to output the target
torque Te*. The CVTECU 359 receives the target rotation speed Nin*
and actuates and controls the first actuator 356 and the second
actuator 357 to make the rotation speed Nin of the input shaft 351
approach to the target rotation speed Ni*.
[0068] As described above, in the motor vehicle 320 of the second
embodiment, the drive control sets the target rotation speed Ne*
and the target torque Te* of the engine 22 by distributing the
rotation speed Ni for in-cylinder injection and the rotation speed
Np for port injection by the allocation rate k of fuel injection
from the in-cylinder fuel injection valves 125 to fuel injection
from the port fuel injection valves 126. Here the rotation speed Ni
for in-cylinder injection is set according to the operation curve
for in-cylinder injection in the operation of the engine 22 with
fuel injection from only the in-cylinder fuel injection valves 125.
The rotation speed Np for port injection is set according to the
operation curve for port injection in the operation of the engine
22 with fuel injection from only the port fuel injection valves
126. The drive control of the motor vehicle 320 then sets the
target rotation speed Ni* of the input shaft 351 and controls the
engine 22 and the CVT 350 to drive the engine 22 at a specific
drive point defined by the target rotation speed Ne* and the target
torque Te* and to ensure output of the torque demand Tout* to the
output shaft 352 or the driveshaft. This arrangement enables the
engine 22 to be driven in the appropriate operating conditions and
ensures output of the torque demand Tout* to the output shaft 352
even in the state of shared fuel injection from the in-cylinder
fuel injection valves 125 and from the port fuel injection valves
126. When the fuel consumption-priority operation curves are set to
the working operation curves, this arrangement enables efficient
operation of the engine 22 and ensures output of the torque demand
Tout* to the output shaft 352 even in the state of shared fuel
injection from the in-cylinder fuel injection valves 125 and from
the port fuel injection valves 126.
[0069] In the absence of the high torque request, the motor vehicle
320 of the second embodiment sets the fuel consumption-priority
operation curves to both the working operation curve for
in-cylinder injection and the working operation curve for port
injection, sets the target rotation speed Ne* and the target torque
Te* of the engine 22 according to the fuel consumption-priority
operation curves, and controls the engine 22 and the CVT 350. In
the presence of the high torque request, on the other hand, the
motor vehicle 320 of the second embodiment sets the high torque
operation curves to both the working operation curve for
in-cylinder injection and the working operation curve for port
injection, sets the target rotation speed Ne* and the target torque
Te* of the engine 22 according to the high torque operation curves,
and controls the engine 22 and the CVT 350. This arrangement
enables the engine 22 to be driven in the appropriate operating
conditions and ensures output of the torque demand Tout* to the
output shaft 352 even in the state of shared fuel injection from
the in-cylinder fuel injection valves 125 and from the port fuel
injection valves 126 with a change of the constraint to set the
drive point of the engine 22 in response to the high torque
request.
[0070] In the motor vehicle 320 of the second embodiment, the belt
CVT 350 is applied for the stepless speed change device. This belt
CVT 350 may be replaced by a toroidal or any other continuous
variable transmission.
[0071] In the motor vehicle 320 of the second embodiment, the drive
control sets the target rotation speed Ne* of the engine 22 to the
target rotation speed Ni* of the input shaft 351 and actuates and
controls the first actuator 356 and the second actuator 357 to make
the rotation speed Nin of the input shaft 351 approach to the
target rotation speed Ni*. One modified flow of the drive control
may set the target rotation speed Ne* of the engine 22 to the
target rotation speed Ni* of the input shaft 351, divide the target
rotation speed Ni* by the rotation speed Nout of the output shaft
352 to set a target gear ratio .gamma.*, and actuate and control
the first actuator 356 and the second actuator 357 to attain the
target gear ratio .gamma.*.
[0072] In the hybrid vehicle 20 of the first embodiment and the
motor vehicle 320 of the second embodiment, the two constraints,
that is, the fuel consumption-priority operation curves and the
high torque operation curves, are provided as the possible
operation curves for in-cylinder injection and the possible
operation curves for port injection. The fuel consumption-priority
operation curves and the high torque operation curves are
selectively used as the working operation curves corresponding to
the presence or the absence of the high torque request. One
possible modification may provide three or more constraints of
operation curves and selectively use these constraints of operation
curves as the working operation curves upon satisfaction of
different conditions. Another possible modification may provide
only one constraint of operation curves, for example, fuel
consumption-priority operation curves, and always use the fuel
consumption-priority operation curves as the working operation
curve for in-cylinder injection and the working operation curve for
port injection.
[0073] In the hybrid vehicle 20 of the first embodiment and the
motor vehicle 320 of the second embodiment, the drive control sets
the target rotation speed Ne* and the target torque Te* of the
engine 22 by distributing the rotation speed Ni for in-cylinder
injection and the rotation speed Np for port injection by the
allocation rate k of fuel injection from the in-cylinder fuel
injection valves 125 to fuel injection from the port fuel injection
valves 126. Here the rotation speed Ni for in-cylinder injection is
set according to the operation curve for in-cylinder injection in
the operation of the engine 22 with fuel injection from only the
in-cylinder fuel injection valves 125. The rotation speed Np for
port injection is set according to the operation curve for port
injection in the operation of the engine 22 with fuel injection
from only the port fuel injection valves 126. One modified flow of
the drive control may set the target rotation speed Ne* and the
target torque Te* of the engine 22 by distributing a first rotation
speed N1 and a second rotation speed N2 by the allocation rate k of
fuel injection from the in-cylinder fuel injection valves 125 to
fuel injection from the port fuel injection valves 126. Here the
first rotation speed N1 is set according to a first operation curve
used in operation of the engine 22 with fuel injection from the
in-cylinder fuel injection valves 125 and fuel injection from the
port fuel injection valves 126 at a preset first allocation rate,
for example, 0.1. The second rotation speed N2 is set according to
a second operation curve used in operation of the engine 22 with
fuel injection from the in-cylinder fuel injection valves 125 and
fuel injection from the port fuel injection valves 126 at a preset
second allocation rate, for example, 0.9.
[0074] In the hybrid vehicle 20 of the first embodiment and the
motor vehicle 320 of the second embodiment, the drive control sets
the target rotation speed Ne* and the target torque Te* of the
engine 22 by distributing the rotation speed Ni for in-cylinder
injection and the rotation speed Np for port injection by the
allocation rate k of fuel injection from the in-cylinder fuel
injection valves 125 to fuel injection from the port fuel injection
valves 126. Here the rotation speed Ni for in-cylinder injection is
set according to the operation curve for in-cylinder injection in
the operation of the engine 22 with fuel injection from only the
in-cylinder fuel injection valves 125. The rotation speed Np for
port injection is set according to the operation curve for port
injection in the operation of the engine 22 with fuel injection
from only the port fuel injection valves 126. Any other technique
may be applied to compute the target rotation speed Ne* and the
target torque Te* of the engine 22 from the rotation speed Ni for
in-cylinder injection, the rotation speed Np for port injection,
and the allocation rate k. For example, the target rotation speed
Ne* and the target torque Te* of the engine 22 may be set by
distributing the rotation speed Ni for in-cylinder injection and
the rotation speed Np for port injection by the allocation rate k
with weighting factors of in-cylinder injection and port injection.
In another example, the target rotation speed Ne* and the target
torque Te* of the engine 22 may be set by distributing the rotation
speed Ni for in-cylinder injection and the rotation speed Np for
port injection by a modified allocation rate, which is obtained by
slow grading the allocation rate k.
[0075] In the hybrid vehicle 20 of the first embodiment and the
motor vehicle 320 of the second embodiment, the power-driven
high-pressure fuel pump 64 is used to apply a pressure to the
supply of fuel through the delivery pipe 66. A mechanically-driven
high-pressure fuel pump by the crankshaft 26 of the engine 22 or by
a camshaft linked with the crankshaft 26 may be used alternatively
to apply a pressure to the supply of fuel through the delivery pipe
66.
[0076] The technique of the invention is applicable to any vehicle
or automobile that is equipped with the engine 22 having both the
in-cylinder fuel injection valves 125 and the port fuel injection
valves 126 and has a torque transmission device or mechanism of
converting the output power of the engine 22 driven at an arbitrary
drive point by torque conversion and transmitting the converted
power to an axle, as described in the first embodiment and the
second embodiment. The invention is not restricted to such vehicles
or automobiles. The power output apparatus equipped with the engine
22 having both the in-cylinder fuel injection valves 125 and the
port fuel injection valves 126 and with the torque transmission
device or mechanism may be mounted on any other moving bodies
including train cars, ships, boats, and aircraft and may be
incorporated in stationary equipment. The technique of the
invention is not restricted to the power output apparatus or the
vehicle but may be actualized as a control method of the power
output apparatus or a control method of the vehicle.
[0077] The embodiment discussed above is to be considered in all
aspects as illustrative and not restrictive. There may be many
modifications, changes, and alterations without departing from the
scope or spirit of the main characteristics of the present
invention. The scope and spirit of the present invention are
indicated by the appended claims, rather than by the foregoing
description.
[0078] The disclosure of Japanese Patent Application No.
2005-186678 filed Jun. 27, 2005 including specification, drawings
and claims is incorporated herein by reference in its entirety.
* * * * *